Why is the object not moving along the curve path?
What you need to do when you want an object to correctly follow the curve is to put both the curve and the object origin at the exact same place. So here:

Select the curve, press ShiftS &gt; Cursor to Selected
Select the object (for example tube) and press ShiftS &gt; Selection to Cursor
Give your object a Curve modifier, find the right Deform Axis (here -Z)
The object is a bit shifted, it's because you've rotated it and didn't apply the rotation, you need to apply (ShiftA)
If you want the curve to go in the opposite direction, switch to Edit mode, right click and Switch Direction